/**
***********************************************************************
*
* Copyright 2011 Stefan Wöhle
*
* This file is part of PixelMath
*
* PixelMath is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* PixelMath is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with PixelMath. If not, see <http://www.gnu.org/licenses/>.
*
***********************************************************************
*/

#ifndef SUBTRACTION_H
#define SUBTRACTION_H

#include "operator.h"

/*********************************************************
 *
 *  Subtraction
 *
 *  Derived from Operator. value() returns the difference of
 *  the two subformulas.
 *
 **********************************************************/

class Subtraction : public Operator
{
    Q_OBJECT
public:
    explicit Subtraction(QObject *parent = 0);
    double value(int x, int y); // throws FormulaException
    QString label();
};

#endif // SUBTRACTION_H
